[Nailfold capillaroscopy-Principles and clinical application].

Nailfold capillaroscopy is a rapid and easily applicable differential diagnostic technique that allows direct visualization of the microcirculation. Abnormal findings in nailfold capillaroscopy are closely associated with connective tissue diseases, such as systemic sclerosis. The clinical manifestation of impaired microcirculation is Raynaud's phenomenon, which is a classical symptom of connective tissue diseases. Nailfold capillaroscopy is increasingly used in various fields of medicine, therefore it is important to define methods for the acquisition and analysis of the results of nailfold capillary and to have a uniform definition of abnormal capillaries. This article discusses image acquisition and analysis, various capillaroscopic techniques, normal and abnormal capillaroscopic features and their significance, scoring systems and reliability of image acquisition and interpretation.